negative to negative to negative

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i want to enlarge a negative onto a 4X5 ortho neg. then of course i will have to contact print onto yet another 4X5 neg to get a neg to enlarge with. does anyone know the f stop and times involved in this process? also, does anyone know how much detail is lost when you enlarge from a neg onto another neg? thanks

-- david clark (doc@ellensburg.com), February 02, 1999

Answers

Ortho film is a similar speed to paper. To get the optimum exposure, just do test strips, as you would with paper. You shouldn't lose any detail.

-- Alan Gibson (Alan.Gibson@technologist.com), February 03, 1999.

If your goal is to produce a 4x5 negative from a smaller (35mm) negative for alternative contact printing. It's eaiser to use Kodak SO-132 duplicating film. It will create a postive image of your negative (i.e. a negative) in one step.

-- Christopher H. Esser (esserc@stricom.army.mil), February 03, 1999.

There are many ways to do this and the times, etc. will depend on the film and chemicals you use, the dilution, the exposure, etc. etc. The only way to find out for yourself is to test, as someone else suggested. You unfortunately will gain contrast, and lose some detail, each step along the way. The loss in going from the negative to the positive isn't great but there is a greater loss when you go from the positive to the negative. Many people use APH lith film sold by Freestyle Sales. It is relatively inexpensive (much less expensive than Kodak dupe film) and comes in a variety of sizes (Kodak dupe film only goes up to 8x10). There is a ton of information about making enlarged interpositives and negatives in the alt.photo newsgroup archives. Also, two very good methods for doing this are discussed in detail in Issue #2 of The World Journal of Post Factory Photography which you can order for about $5. I don't have an e mail address for The World Journal handy nor do I have the URL for the archives handy but if you want to pursue either let me know and I'll get them for you. Brian

-- Brian Ellis (beellis@gte.net), February 05, 1999.

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